Mercury Force Outboard 50 hp charging battery?

[Rawhawk]

My boat mechanic tells me that there is nothing I can do to keep my batteries charged while on the water. Says the "stater"? is weak and only produces about 2 amps at full throttle. New stater not an option, but definatley need to find a way to charge the batteries either from the motor or other source while on the water. The engine is a 50 hp mercury force. Thanks

 

[Rawhawk]

Re: Mercury Force Outboard 50 hp charging battery?

sorry just realized my post doesn't belong here.

 

[JB]

Re: Mercury Force Outboard 50 hp charging battery?

No prob, Rawhawk. Moved to Force trooubles.

 

[roscoe]

Re: Mercury Force Outboard 50 hp charging battery?

What year is your motor?<br /><br />Is he sure it isn't just a bad rectifier?<br /><br />Did he actually test it at full throttle?<br /><br />When new, the older ones only put out about 1 amp at 1000rpm, and 7 amps at full throttle.<br /><br />If the motor is generating enough current to run the ignition, then the 2 amp output is only needed to replenish the charge that was lost during starting. It should be enough. I bet your rectifier is shot.<br /><br />The 25 and 35hp only put out 2 amps when they were new. <br /><br />Do you have a tack, and if so, is it working?

 

[Rawhawk]

Re: Mercury Force Outboard 50 hp charging battery?

the tach works and it is a 1998 year. But it seems like as I was out on the water that the amp meter just kept going down as we played the stereo, obviously. But my point is that as I had the motor wrapped up cruising across the lake it would never charge. The amp meter would never go back up?

 

[roscoe]

Re: Mercury Force Outboard 50 hp charging battery?

OK, so your tach is working, so your rectifier sounds like it is ok.<br />Lights, stereo, bilge pump, or livewell will be an added drain and your system will not recharge the battery. Could be the output to the coils is very low also, causing the motor to continuously draw from the battery. Don't know for sure.<br /><br />But if a new stator is not an option, then I think you are up a creek without a motor. <br /><br />A new stator will cost $159.62, or $210 for the real good one.<br />Not hard to replace, if the flywheel comes off easily.

 

[chuckz]

Re: Mercury Force Outboard 50 hp charging battery?

Do you have an ammeter or voltmeter? If it's a voltmeter and it never goes uo, your rectifier is not working (sorry roscoe). If the tach works and you have no charging voltage the rectifier isn't shorted but is probably open.<br /><br />There is a post here somewhere on troubleshooting the rectifier with a ohmmeter. It's well written and worth searching for.

 

[roscoe]

Re: Mercury Force Outboard 50 hp charging battery?

Yes, could be as LI Chuck says, the rectifier may be bad, ...<br /><br />Gotta figure that the wrench would've checked for voltage to the battery, along with all the other tests, but who knows.<br /><br />Did the mechanic provide you with any of the readings he took?<br /><br />IF the output is that low, and he's running a big draw stereo, it isn't gonna keep up. Why not put in another battery, a deep cycle, and run the stereo off of that. Then charge it manually at the dock/home between outings?<br /><br />Either do as the mechanic says, do nothing, or get a troubleshooting manual and check everything out for yourself. Then decide if you are going to fix it or not.<br /><br />You are living on borrowed time.<br /><br />Get some actual test readings and go from there.<br />That motor should put out 8 amp charge at 1000-1400rpm, 14 amp at 3500 rpm.